Molding machine



Cd. 18, 1932. D J. CAMPBELL 1,883,542

MOLDING MACHINE Filed Sept. 29, 1950 2 Sheets-Sheet l box-n16 Q. 01mm MM WW Oct. 18, 1932.

D. .1. CAMPBELL MOLDING MACHINE Filed Sept. 29. 1950 2 Sheets-Sheet QPfome s Patented Oct. 18, 1932 main) .1. CAMPBELL, or nusxnson nmsn'rs, MIGHIGAN MOLDING MACHINE Application filed September 29, 1930. Serial -Ko.'84,989.

This invention relates to molding machines and more particularly to that type of machine for the purpose of squeezing the sand in a flask around a pattern to produce a mold.

Molding machines of this general type in the past have been designed to compress the sand in the flask by from the upper side. of the flask wherein the pattern was located at the lower side of the flask and obviously the portion of the sand. in

the flask immediately surrounding the pattern was that which should be most firmly compressed but was most remotely located,

from the point of pressure. The flask is. usually provided with, bars extendingacross its upper open side opposite the side from which the pattern is located for the purpose of re tainin the compressed sand in the flaskand these ars together with the frictional resistance of the sides of the flask and the. re-

sistance of the sand itself. to be compressed prevented. a close compression-of the sand at the bottom of the flask around the pattern.

The present invention isintended to ob.- viate the diiflculties above referred to and to make it possible and expedient to compress the sand firmly throughout all portions of the mold thereby resulting in a firm: compactness of the sand around the patternand adjacent the mold cavity. The invention provides various novel features of construction and ar rangement as hereinafter more fully described and particularly pointed out in the claims, reference being had to the accompany in-g: drawings, in which,

'Fig. 1 is a verti al elevation, partly in section, of a molding machine embodying this invention shown arrangedfor the beginning of the operation. I

Fig- 2 illustrates the same device in position at the completion of the squeezing operation, some of the parts be m-g shown in elevation which are shown in section in Fig; 1.

Fig. 3 illustrates the device partly inside elevation and partly in section at the completion of the operation with the pattern and pattern plate lowered and the pressure head raised and the completed mold supported in position to. be removed,

forcing it downwardly Fig. 4 is 'a'sectional plan onthe line H of Fig. 1, and r V Fig. dis a fragmentary enlarged section of the eccentric adjusting means on the line 5-5 elf-Fi s Like numbers refer to like parts mall the figures. ,v V i 1 I Th machine embodying this invention comprises a base 1 on which is formed a Vere tical cylinder 2 having a closed lower end and an open upper end and a piston'3lis located in the cylinder and isvertically'reciprocable,itsnpper end projecting fromthe upper end of the cylinder and being provided with a supporting plate 4. A passage 5 communicates with the lower end of the cylinder 2 and a pipe 6- is connected to the passage 5through which fluid under pressure such as compressed air may be admitted to the cylinder to raise the piston 3. V Appattern plate surface of the supporting plate 4- and earries a pattern 8 on its upper surface and a supporting frame 9, having a renewable lining 10, surrounds the supporting frame 4 and the pattern plate 7 and is adjustably supported in fixed position by rods 11 which are threaded into extensions 12 from the cylinder. The inner shape and dimensionso-f the; frame 9 are preferably the same as those 7 is mountedjonthe upper 1 of. the flask 13 in which the mold is tobe f formed. The flask 13 is of conventional type, open at its upper and lowerends' and preferably provided with bars 1d extending between its sides near its upper end. I Avertieal guideway 15 extends upwardly fromthe; base let the rear of the cylinder 2 and the parts mounted'thereon and carries a slide 16 upon which are mounted a, swing: ing pressure head 17 and parts for actuating said pressure head. The slide is adapted for vertical adjustment by means of a rod 18pxtendin-g upwardly from the base and passing through a lug 19 on. the slide, the rod 18 beingscrewthreaded andprovided with nuts 20 above and below the lug.

The pressure head 17 is mounted at the forward end of a swinging arm 21 which is pivoted at 22 on the slide 16. An opera-ting lever 23 ispivoted on the slide 16 and is connected to the piston rod 24 of a piston 24a within the cylinder 25, the cylinder preferably being mounted on the slide 16 by means of trunnions 25a. The forward end of the operating lever23 is connected by a link 26 with the rear end of the swinging arm 21. A lug 27 on the forward end of the lever 23 extends into the plane of the link 26 and engages an edge of the link when the lever 23 is raised to its extreme position as shown in Fig. 2 and the parts are so designed that in this extreme position the centers of the pivotal connections of the link 26 and the lever 23 are in substantial alinement forming a stiff connection to rigidly hold the rear end of the swingingarm 21 raised with its forward end carrying the pressure head 17 in lowered position. The pivoted end of the lever 23 is provided with an eccentric adjustment which may be used to govern the lowered position of the pressure head 17 when the lever and link 26 are in stiff connecting position. The eccentric adjustment comprises a shaft 28 on which the lever 23 is pivoted and the respective ends of the shaft are mounted in and keyed-to eccentric sleeves 28a rotatable in the slide 16 and fixed by removable keys 28b. Conduits 29 and 30 communicate with the respective upper and lower ends of the cylinder 25 to supply fluid under pressure, such as compressed air, which actuates' the piston in the cylinder.

The pressure head 17 is mounted at the forward end of the arm 21 for limited universal movement by means of a semi-spherical member 31 on the pressure head which fits into a corresponding semi-spherical socket 32 at the forward end of the arm 21 and a bolt 33 fastened to the pressure head extends through an opening on the arm 21 and is provided with a nut 34 at its upper end and a rubber pad 35 is interposed between the nutand the upper surface of the arm and is sufliciently'yieldable to permit small movement of the bolt and nut to accommodate small rocking movement of the pressure head. The pressure head is prevented from rotation relative to the arm by means of a pin 36 which slidably enters an opening in a boss 37 on the arm. This pin connection permits a slight rocking movement of the pressure head relative to the arm but prevents rotation thereof.

Operation the pattern plate at a proper distance for the operation. The pressure head is adjusted by raising or lowering the slide 16 so that 1t Wlll fit closely against the upper edge of the flask 13 when it is in lowered position and if necessary the eccentric pivotal mounting of the lever 23 is adjusted so that the said lever and the link 26 will be in stiff connecting posltion when the lever is moved to the extreme limit of its stroke with the lug 27 in engagement with an edge of the link 26.

After the machine has been properly set up and adjusted for operation the piston 3 is lowered tothe bottom of its stroke and a flask 13 is placed upon the top of the supporting frame 9. When so arranged the supporting frame 9 constitutes a downward extension of the flask and the flask and supporting frame above the pattern plates are filled with sand and sand is also provided on the flask above its upper edge. A flask plate 13a may be usedas an upper extension of the flask to receive the sand and be removed after the sand has been deposited in order to correctly govern the amount of sand extending above 5 the flask. At this point of the operation the loose sand fills the flask surrounding the flask bars 14k and extends below the flask around the pattern and into the supporting frame 9 and also extends above the flask to some extent so that the loose sand occupies a considerably greater volume than the capacity of the flask itself.

The first operation of compressing the sand consists of lowering the pressure head 17 by action of the piston 24m within the cylinder 25 by injecting compressed air below it through the conduit 30 which will swing the lever 23 upwardly and acting through the the link 26 and lever 23 are substantially in allnement formlng a rigid brace or stiff con nection to hold the lever 21 in its position with the pressure head lowered against the upper side of the flask. The action of the pressure head against the sand has been to compress it to some extent within the flask but the greatest amount of compression has occurred at the upper side of the flask, the sand having been compressed firmly around the flask bars 14 and to some extent around the pattern itself.

The next operation is to admit compressed air through the conductor 6 and passage 5 to the lower end of the cylinder 2 which raises the piston 3 and carries the supporting plate 4, pattern plate 7 and pattern 8 upwardly with relation to the flask which is firmly held in place by the pressure head '17 against its upper edge. This movement continues until the stops 4a formed on extensions of the supporting plate 4 engage the'lower edge of the frame 9 which limits the movement of the parts in upper direction and at which loca tion the upper surface of the pattern plate is flush with the lower edge of the flask 13. The latter operation has resulted in com-- pressing the lower portion of the sand which lay around the pattern itself compactly into the flask and all of the loose sand which originally occupied aspace considerably greater than the capacity of the flask has been compressed, first from theupper side and then from the lower side, wholly within the flask and the resulting condition of the sand is that all portions of it are tightly compressed within the flask and most essentially around the pattern so that when'the pattern is removed the walls of the moldcavity are extremely firm.

Completion of the operation obviously consists of lowering the piston 3 and raising the pressure head 17 leaving the flask with the sand supported therein resting upon the supporting frame 9 from where it may readily be removed and anotherflask located in its place to repeat the operation.

I claim: p

' 1. A molding machine comprising, a base, means for supporting a flask having open upper and lower sides on said base and a pattern associated with said flask, said flask being adapted to receive loose sand surrounding said pattern, said base, and means movablymounted on said slide and located adjacent the flask for compressing the sand therein.

2. A molding machine comprising, a base, means for supporting a flask having open upper and lower sides on said base and a pattern associated with said flask, said flask being adapted to receive loose sand surrounding said pattern, a slide vertically adjustable on said base, a pressure head pivotally mounted upon said slide and movable toward the open upper side of the flask to compress the sand therein and means for swinging said pressure head.

3. A molding machine comprising, a base, means for supporting a flask having open upper and lower sides on said base and a pattern associated with said flask, said flask be ing adapted to receive loose sand surrounding said pattern, a slide vertically adjustable on said base, a pressure head pivotally mounted upon said slide and movable toward the open upper side of the flask to compress the sand therein and means for swinging said pressure head, said means including levers movable to stiff-locking position when the pressure head is in lowered position.

l. A molding machine comprising, a base,

a slide vertically adjustable on a cylinder on said base, a pistonin said cylinasupporting frame having an open upperside supported on said base, said support: ing frame being-adapted to support a flask having-open upper and lower sides, a pattern plate and pattern movably located with in said supporting frame and supported by said piston, said flask and supporting frame being adapted to receive sand above said pattern plate, means for varying the location of said supporting frame relative to said pattern plate, a pressure head movable toward and engageable with the upper edge of said flask and means for injecting fluid under pressure into said cylinder to raise said piston.

5. A molding machine comprising, a base, a vertical cylinder'supported on the base, a piston in said cylinder, a supporting frame having an openupper side supported on said base and adapted to support a flask having open upper and lower sides, a pattern plate and pattern movably located within said supporting frame and supported by said piston,

a vertical guide supported on said base, a

slide mounted in said guide, a pressure head pivotally mounted on said slide and adapted to swing toward and into engagement with the upper edge of saidflask, means mounted on said slide fo'r'swinging said pressure head and means for injecting fluid under pressure into said cylinder to raise the piston and pattern plate.

6. A molding machine comprising, a base, a vertical cylinder supported on the base,'a piston in said cylinder, a supporting frame having an open upper side supported on said base and adapted to support a flask having open upper and lower sides, a patternplate and pattern movably located within said supporting frame and supported by said piston, a vertical guide supported on said base, a slide mounted in said guide, a pressure head pivotally mounted on said slide and adapted to swing toward and into engagement with the upper edge of said flask, means mounted 011 said slide for swinging said pressure head, means associated with said operating means for locking said pressure head in lowered position and means for injecting fluid under pressure into said cylinder to raise the piston and pattern plate.

7. A molding machine comprising abase, means for supporting a flask having an open upper side onsaid base and a pattern associated with said flask, said flask being adapted to receive loose sand surrounding said pattern, a pressure head pivotally mounted upon said base and located at the top side of the flask and movable toward the flask tocompress the sand therein and means for swinging said pressure head, said means including levers movable to stiff-locking position for the purpose described. r

8. In a device of the character described,

a base, means for supporting a flask having open upper and lower sides on the said base and a pattern associated with said flask, this flask being adapted to receive loose sand surrounding said pattern, a pressure head, a lever pivotally mounted on the base, said pressure head having a semi-spherical member engaging into a corresponding semispherical socket on the lever and means for yleldably maintaining the said socket in the said recess for the purpose described.

9. In a molding machine having an open flask adapted to receive a pattern therein and loose sand over the pattern, the combination of a pressure head movable toward the open side of the flask to compress the sand therein, hydraulic means for moving said pressure head and holding the same in a predetermined position, and additional means to also hold the pressure head against return movement.

10. In a molding machine of the class de scribed, a base, flask adapted to be received upon the frame, a pattern plate, means to move said pattern plate through said frame to its operative position and stop means between said last mentioned means and the frame whereby the pattern plate is positioned in a predetermined position relative to the said flask.

In testimony whereof I afiix my signature.

DONALD J. CAMPBELL.

a frame mounted thereon, a 

